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SAP on zSeries High Availability for SAP on zSeries Using Autonomic Computing Technologies SC33-8206-00

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  • SAP

    on

    zSeries

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    SC33-8206-00

    ���

  • SAP

    on

    zSeries

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    SC33-8206-00

    ���

  • Note:

    Before

    using

    this

    information

    and

    the

    product

    it

    supports,

    be

    sure

    to

    read

    the

    general

    information

    under

    “Notices”

    on

    page

    317.

    First

    Edition

    (August

    2004)

    This

    edition

    applies

    to

    v

    SAP

    R/3

    release

    4.6D

    v

    mySAP:

    SAP

    Web

    Application

    Server

    6.20

    v

    SAP

    NetWeaver

    ’04:

    SAP

    Web

    Application

    Server

    6.40

    v

    Version

    1

    Release

    2

    of

    z/OS

    (5694-A01)

    v

    AIX

    Release

    5.1

    (5765-E61)

    and

    higher

    supported

    5.x

    versions

    v

    Linux

    for

    zSeries

    (for

    distribution

    details,

    see

    SAP

    Note

    81737)

    v

    IBM

    DB2

    Universal

    Database

    for

    OS/390

    Version

    6

    (5645-DB2),

    IBM

    DB2

    Universal

    Database

    for

    OS/390

    and

    z/OS

    Version

    7

    (5675-DB2),

    and

    DB2

    Universal

    Database

    for

    z/OS

    Version

    8

    (5625-DB2).

    v

    IBM

    Tivoli

    System

    Automation

    for

    OS/390

    V2.2

    v

    IBM

    Tivoli

    System

    Automation

    for

    Linux

    V1.1

    v

    Windows

    2000

    and

    to

    all

    subsequent

    releases

    and

    modifications

    until

    otherwise

    indicated

    in

    new

    editions

    or

    Technical

    Newsletters.

    Order

    publications

    through

    your

    IBM

    representative

    or

    the

    IBM

    branch

    office

    serving

    your

    locality.

    Publications

    are

    not

    stocked

    at

    the

    address

    given

    below.

    IBM

    welcomes

    your

    comments.

    A

    form

    for

    your

    comments

    appears

    at

    the

    back

    of

    this

    publication.

    If

    the

    form

    has

    been

    removed,

    address

    your

    comments

    to:

    IBM

    Deutschland

    Entwicklung

    GmbH

    Department

    3248

    Schoenaicher

    Strasse

    220

    D-71032

    Boeblingen

    Federal

    Republic

    of

    Germany

    FAX

    (Germany):

    07031-16-3456

    FAX

    (Other

    Countries):

    (+49)+7031-16-3456

    Internet

    e-mail:

    [email protected]

    World

    Wide

    Web:

    http://www.ibm.com/servers/eserver/zseries/software/sap

    http://www.ibm.com/servers/eserver/zseries/zos

    http://www.ibm.com/servers/s390/os390

    When

    you

    send

    information

    to

    IBM,

    you

    grant

    IBM

    a

    nonexclusive

    right

    to

    use

    or

    distribute

    the

    information

    in

    any

    way

    it

    believes

    appropriate

    without

    incurring

    any

    obligation

    to

    you.

    ©

    Copyright

    International

    Business

    Machines

    Corporation

    2004.

    All

    rights

    reserved.

    US

    Government

    Users

    Restricted

    Rights

    Use,

    duplication

    or

    disclosure

    restricted

    by

    GSA

    ADP

    Schedule

    Contract

    with

    IBM

    Corp.

    http://www.ibm.com/servers/eserver/zseries/software/saphttp://www.ibm.com/servers/eserver/zseries/zoshttp://www.ibm.com/servers/s390/os390

  • Contents

    Figures

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . vii

    Tables

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . ix

    About

    this

    document

    .

    .

    .

    .

    .

    .

    .

    .

    . xi

    Who

    should

    read

    this

    document

    .

    .

    .

    .

    .

    .

    . xi

    Important

    remarks

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xi

    Conventions

    and

    terminology

    used

    in

    this

    document

    xi

    Highlighting

    conventions

    .

    .

    .

    .

    .

    .

    .

    . xiii

    Syntax

    diagrams

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xiii

    Prerequisite

    and

    related

    information

    .

    .

    .

    .

    .

    . xiv

    How

    to

    send

    in

    your

    comments

    .

    .

    .

    .

    .

    .

    . xiv

    Content

    of

    this

    document

    .

    .

    .

    .

    .

    .

    .

    .

    . xiv

    Introducing

    high

    availability

    and

    automation

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    . xvii

    High

    availability

    definitions

    .

    .

    .

    .

    .

    .

    .

    . xix

    Degrees

    of

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    . xix

    Types

    of

    outages

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xx

    Tivoli

    System

    Automation’s

    autonomic

    computing

    self-healing

    technologies

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xxi

    High

    availability

    and

    automation

    objectives

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xxii

    No

    planned

    outages

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xxii

    Failover

    support

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . xxiii

    Reduced

    operator

    errors

    .

    .

    .

    .

    .

    .

    .

    . xxiii

    Health

    check

    for

    application

    problems

    .

    .

    .

    . xxiii

    Overview

    of

    the

    high

    availability

    solution

    for

    SAP

    xxiii

    High

    availability

    of

    an

    SAP

    system

    .

    .

    .

    .

    . xxiii

    Automation

    of

    an

    SAP

    system

    .

    .

    .

    .

    .

    . xxiv

    Benefits

    of

    Tivoli

    System

    Automation

    .

    .

    .

    . xxiv

    Part

    1.

    Database

    considerations

    for

    high

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 1

    Chapter

    1.

    SAP

    availability

    benefits

    provided

    by

    zSeries

    .

    .

    .

    .

    .

    .

    .

    .

    . 3

    Features

    of

    the

    zSeries

    hardware

    architecture

    .

    .

    . 3

    Features

    of

    z/OS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 4

    List

    of

    z/OS

    availability

    features

    .

    .

    .

    .

    .

    .

    . 5

    Availability

    features

    and

    benefits

    with

    zSeries

    Parallel

    Sysplex

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 6

    6

    List

    of

    zSeries

    Parallel

    Sysplex

    availability

    features

    6

    Features

    of

    DB2

    UDB

    for

    z/OS

    .

    .

    .

    .

    .

    .

    .

    . 7

    List

    of

    DB2

    UDB

    for

    z/OS

    availability

    features

    .

    . 7

    List

    of

    DB2

    UDB

    for

    z/OS

    availability

    features

    with

    data

    sharing

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 13

    Non-disruptive

    software

    changes

    .

    .

    .

    .

    .

    . 14

    DB2

    UDB

    for

    z/OS

    improvements

    .

    .

    .

    .

    .

    . 14

    SAP

    benefits

    and

    availability

    scenarios

    .

    .

    .

    .

    . 15

    Chapter

    2.

    DB2

    data

    sharing

    on

    zSeries

    Parallel

    Sysplex

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 17

    Why

    Parallel

    Sysplex

    and

    data

    sharing

    for

    SAP?

    .

    . 17

    Parallel

    Sysplex

    architecture

    .

    .

    .

    .

    .

    .

    .

    .

    . 17

    DB2

    data

    sharing

    architecture

    .

    .

    .

    .

    .

    .

    .

    . 18

    SAP

    sysplex

    failover

    architecture

    .

    .

    .

    .

    .

    .

    . 19

    Chapter

    3.

    Architecture

    options

    and

    trade-offs

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 23

    DB2

    data

    sharing

    design

    options

    for

    SAP

    .

    .

    .

    . 23

    Option

    0:

    Single

    DB2

    member

    with

    passive

    (inactive)

    standby

    member

    .

    .

    .

    .

    .

    .

    .

    . 24

    Option

    1:

    Two

    active

    DB2

    members

    without

    passive

    standby

    members

    .

    .

    .

    .

    .

    .

    .

    . 25

    Option

    2:

    Two

    active

    DB2

    members,

    each

    with

    a

    passive

    standby

    member

    in

    the

    same

    LPAR

    .

    . 30

    Option

    3:

    Two

    active

    DB2

    members,

    each

    with

    a

    passive

    standby

    member

    in

    an

    independent

    LPAR

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 31

    How

    many

    data

    sharing

    groups?

    .

    .

    .

    .

    .

    . 31

    How

    many

    sysplexes?

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 32

    How

    many

    data

    sharing

    members?

    .

    .

    .

    .

    . 32

    Failover

    design

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 34

    ICLI

    design

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 35

    How

    many

    ICLI

    servers?

    .

    .

    .

    .

    .

    .

    .

    .

    . 35

    Transition

    from

    ICLI

    to

    DB2

    Connect

    .

    .

    .

    .

    . 36

    Chapter

    4.

    Backup

    and

    recovery

    architecture

    in

    data

    sharing

    .

    .

    .

    .

    .

    . 37

    Data

    sharing

    backup/recovery

    considerations

    .

    .

    . 37

    Data

    sharing

    recovery

    environment

    .

    .

    .

    .

    . 37

    Tablespace

    recovery

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 39

    Recovering

    pages

    on

    the

    logical

    page

    list

    .

    .

    . 41

    Data

    sharing

    impact

    on

    SAP

    recovery

    procedures

    42

    Object-based

    backup:

    online

    and

    offline

    .

    .

    .

    . 42

    Online

    volume-based

    backup

    without

    the

    BACKUP

    SYSTEM

    utility

    .

    .

    .

    .

    .

    .

    .

    .

    . 43

    Establishing

    a

    group-level

    point

    of

    consistency

    46

    Recovery

    to

    the

    current

    state

    .

    .

    .

    .

    .

    .

    . 46

    Recovery

    to

    a

    previous

    point

    in

    time

    before

    DB2

    V8

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 47

    New

    utilities

    in

    DB2

    V8

    for

    online

    backup

    and

    point-in-time

    recovery

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 50

    Data

    sharing

    considerations

    for

    disaster

    recovery

    .

    . 51

    Configuring

    the

    recovery

    site

    .

    .

    .

    .

    .

    .

    . 51

    Remote

    site

    recovery

    using

    archive

    logs

    .

    .

    .

    . 52

    Using

    a

    tracker

    site

    for

    disaster

    recovery

    .

    .

    . 53

    GDPS

    infrastructure

    for

    disaster

    recovery

    .

    .

    . 54

    Homogeneous

    system

    copy

    in

    data

    sharing

    .

    .

    .

    . 58

    Planning

    for

    homogeneous

    system

    copy

    in

    data

    sharing

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 58

    Designing

    homogeneous

    system

    copy

    in

    data

    sharing

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 60

    Part

    2.

    Network

    considerations

    for

    high

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 63

    ©

    Copyright

    IBM

    Corp.

    2004

    iii

  • Chapter

    5.

    Network

    considerations

    for

    high

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 65

    Introduction

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 65

    General

    recommendations

    .

    .

    .

    .

    .

    .

    .

    .

    . 66

    Hardware

    considerations

    .

    .

    .

    .

    .

    .

    .

    .

    . 66

    z/OS

    communication

    software

    considerations

    .

    . 66

    Considerations

    for

    the

    Linux

    for

    zSeries

    application

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 66

    Multiple

    Linux

    for

    zSeries

    guests

    under

    z/VM

    66

    SAP

    sysplex

    failover

    recovery

    mechanism

    .

    .

    .

    . 69

    OSPF

    protocol

    as

    a

    recovery

    mechanism

    .

    .

    .

    .

    . 70

    Virtual

    IP

    Address

    (VIPA)

    as

    a

    recovery

    mechanism

    71

    Recommended

    setup

    for

    high

    availability

    connections

    between

    client

    and

    server

    .

    .

    .

    .

    . 73

    OSPF

    and

    subnet

    configuration

    aspects

    .

    .

    .

    . 73

    VIPA

    and

    Source

    VIPA

    functions

    on

    remote

    application

    servers

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 74

    Recommended

    setup

    for

    a

    high

    availability

    network

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 75

    Alternative

    recovery

    mechanism

    on

    Windows

    .

    .

    . 76

    z/OS

    VIPA

    usage

    for

    the

    high

    availability

    solution

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 78

    Timeout

    behavior

    of

    the

    client/server

    connection

    over

    TCP/IP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 78

    Timeout

    behavior

    of

    the

    AIX

    application

    server

    79

    Timeout

    behavior

    of

    the

    Linux

    for

    zSeries

    application

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 81

    Timeout

    behavior

    of

    the

    Windows

    application

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 82

    SAP

    maximum

    transaction

    time

    .

    .

    .

    .

    .

    . 83

    Timeout

    behavior

    of

    the

    database

    server

    .

    .

    .

    . 83

    Part

    3.

    Application

    server

    considerations

    for

    high

    availability

    . 87

    Chapter

    6.

    Architecture

    for

    a

    highly

    available

    solution

    for

    SAP

    .

    .

    .

    .

    .

    . 89

    Architecture

    components

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 89

    New

    SAP

    Central

    Services

    replacing

    the

    central

    instance

    concept

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 89

    Network

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 95

    File

    system

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 99

    Database

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 101

    Remote

    application

    server

    and

    sysplex

    failover

    support

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 103

    Application

    design

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 105

    Failure

    scenarios

    and

    impact

    .

    .

    .

    .

    .

    .

    .

    . 106

    Old-style

    central

    instance

    without

    data

    sharing

    106

    Data

    sharing,

    sysplex

    failover,

    double

    network

    (single

    central

    instance)

    .

    .

    .

    .

    .

    .

    .

    .

    . 108

    Enqueue

    replication

    and

    NFS

    failover:

    fully

    functional

    high

    availability

    .

    .

    .

    .

    .

    .

    .

    . 110

    Chapter

    7.

    Planning

    and

    preparing

    an

    end-to-end

    high

    availability

    solution

    . 113

    Software

    prerequisites

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 114

    Naming

    conventions

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 115

    Tivoli

    System

    Automation

    for

    z/OS

    .

    .

    .

    .

    . 115

    Tivoli

    System

    Automation

    for

    Linux

    .

    .

    .

    .

    . 118

    DB2

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 118

    ARM

    policy

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 118

    ICLI

    and

    DB2

    Connect

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 119

    File

    system

    setup

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 119

    File

    systems

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 119

    SAP

    directory

    definitions

    .

    .

    .

    .

    .

    .

    .

    . 120

    NFS

    server

    on

    z/OS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 121

    NFS

    server

    on

    Linux

    for

    zSeries

    .

    .

    .

    .

    .

    . 122

    Tivoli

    System

    Automation

    .

    .

    .

    .

    .

    .

    .

    .

    . 123

    Setup

    of

    Tivoli

    NetView

    and

    Tivoli

    System

    Automation

    for

    z/OS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 123

    Tivoli

    System

    Automation

    for

    Linux

    setup

    .

    .

    . 123

    SAP

    installation

    aspects

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 124

    SAP

    license

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 124

    SAP

    logon

    groups

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 124

    Chapter

    8.

    Customizing

    SAP

    for

    high

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 125

    Installing

    and

    configuring

    SAP

    Central

    Services

    (SCS)

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 125

    Getting

    the

    standalone

    enqueue

    server

    code

    from

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 125

    Configuring

    SAP

    Central

    Services

    .

    .

    .

    .

    . 126

    SAP

    profile

    parameters

    .

    .

    .

    .

    .

    .

    .

    .

    . 127

    Preparing

    SAP

    on

    z/OS

    for

    automation

    .

    .

    .

    . 129

    C-shell

    and

    logon

    profiles

    .

    .

    .

    .

    .

    .

    .

    . 129

    ICLI

    servers

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 130

    SAP

    Central

    Services

    (SCS)

    .

    .

    .

    .

    .

    .

    .

    . 131

    Application

    server

    instances

    .

    .

    .

    .

    .

    .

    . 132

    saposcol

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 135

    rfcoscol

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 135

    saprouter

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 137

    Summary

    of

    start,

    stop

    and

    monitoring

    commands

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 137

    Chapter

    9.

    Change

    management

    .

    .

    . 139

    Updating

    the

    SAP

    kernel

    .

    .

    .

    .

    .

    .

    .

    .

    . 139

    Updating

    the

    SAP

    kernel

    (release

    4.6

    or

    later)

    140

    Rolling

    kernel

    upgrade

    .

    .

    .

    .

    .

    .

    .

    .

    . 141

    Updating

    the

    ICLI

    client

    and

    server

    .

    .

    .

    .

    .

    . 141

    Rolling

    upgrade

    of

    the

    ICLI

    client

    .

    .

    .

    .

    . 142

    Rolling

    upgrade

    of

    the

    ICLI

    server

    .

    .

    .

    .

    . 142

    Updating

    an

    ICLI

    server

    with

    a

    new

    protocol

    version

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 143

    Rolling

    update

    of

    DB2

    Connect

    .

    .

    .

    .

    .

    .

    . 143

    Normal

    FixPak

    installation

    .

    .

    .

    .

    .

    .

    .

    . 143

    Alternate

    FixPak

    installation

    .

    .

    .

    .

    .

    .

    . 144

    Updating

    DB2

    or

    z/OS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 146

    Part

    4.

    Autonomic

    operation

    of

    the

    high

    availability

    solution

    for

    SAP

    . 149

    Chapter

    10.

    Customizing

    Tivoli

    System

    Automation

    for

    z/OS

    .

    .

    .

    .

    . 151

    Preparing

    SA

    for

    z/OS

    for

    SAP

    high

    availability

    151

    Before

    you

    start

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 151

    Setting

    initialization

    defaults

    for

    SA

    for

    z/OS

    (AOFEXDEF)

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 151

    Setting

    the

    region

    size

    for

    NetView

    to

    2

    GB

    .

    . 152

    iv

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • Customizing

    the

    Status

    Display

    Facility

    (SDF)

    152

    Sending

    UNIX

    messages

    to

    the

    syslog

    .

    .

    .

    . 153

    Setting

    MAXFILEPROC

    in

    BPXPRMxx

    .

    .

    .

    . 153

    Defining

    the

    SAP-related

    resources

    .

    .

    .

    .

    .

    . 153

    Overview

    of

    the

    resources

    .

    .

    .

    .

    .

    .

    .

    . 154

    Classes

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 154

    Database

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 155

    SAP

    Central

    Services

    and

    the

    enqueue

    replication

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 159

    Application

    servers

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 166

    SAP

    RED

    local

    applications

    .

    .

    .

    .

    .

    .

    .

    . 171

    NFS

    server

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 173

    saprouter

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 175

    SAP

    local

    application

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 176

    Defining

    superior

    groups

    .

    .

    .

    .

    .

    .

    .

    . 178

    Overall

    picture

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 180

    Summary

    tables

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 181

    Classes

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 181

    Applications

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 181

    Application

    groups

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 182

    Additions

    to

    the

    Automation

    Table

    .

    .

    .

    .

    .

    . 183

    Extension

    for

    DFS/SMB

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 184

    Additions

    to

    the

    SA

    for

    z/OS

    policy

    .

    .

    .

    .

    . 184

    Additions

    to

    SDF

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 186

    Additions

    to

    the

    Automation

    Table

    for

    DFS/SMB

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 186

    Chapter

    11.

    Customizing

    Tivoli

    System

    Automation

    for

    Linux

    .

    .

    .

    . 187

    Overview:

    Tivoli

    System

    Automation

    for

    Linux

    .

    . 187

    SAP

    in

    a

    high

    availability

    environment

    .

    .

    .

    .

    . 187

    Scope

    of

    the

    sample

    SA

    for

    Linux

    high

    availability

    policy

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    . 188

    Setting

    up

    SA

    for

    Linux

    and

    SAP

    .

    .

    .

    .

    .

    .

    . 190

    Establishing

    the

    setup

    .

    .

    .

    .

    .

    .

    .

    .

    . 190

    Installing

    and

    customizing

    SAP

    .

    .

    .

    .

    .

    . 191

    Installing

    SA

    for

    Linux

    .

    .

    .

    .

    .

    .

    .

    .

    . 191

    Making

    NFS

    highly

    available

    via

    SA

    for

    Linux

    191

    Installing

    the

    high

    availability

    policy

    for

    SAP

    192

    Customizing

    the

    high

    availability

    policy

    for

    SAP

    192

    Setting

    up

    SA

    for

    Linux

    to

    manage

    SAP

    resources

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 193

    Setting

    up

    the

    enhanced

    HA

    policy

    for

    SAP

    (including

    the

    NFS

    server

    HA

    policy)

    .

    .

    .

    . 195

    Cleaning

    up

    the

    HA

    policy

    .

    .

    .

    .

    .

    .

    .

    . 196

    Two-node

    scenario

    using

    SA

    for

    Linux

    .

    .

    .

    .

    . 196

    Part

    5.

    Verification

    and

    problem

    determination

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 199

    Chapter

    12.

    Verification

    and

    problem

    determination

    on

    z/OS

    .

    .

    .

    .

    .

    .

    . 201

    Verification

    procedures

    and

    failover

    scenarios

    .

    . 201

    Overview

    of

    the

    test

    scenarios

    .

    .

    .

    .

    .

    .

    . 201

    Test

    methodology

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 203

    Planned

    outage

    test

    scenarios

    .

    .

    .

    .

    .

    .

    . 210

    Unplanned

    outage

    test

    scenarios

    .

    .

    .

    .

    .

    . 217

    Problem

    determination

    methodology

    .

    .

    .

    .

    . 231

    SA

    for

    z/OS

    problem

    determination

    .

    .

    .

    .

    . 231

    Where

    to

    check

    for

    application

    problems

    .

    .

    . 236

    Checking

    the

    network

    .

    .

    .

    .

    .

    .

    .

    .

    . 237

    Checking

    the

    status

    of

    the

    Shared

    HFS

    and

    of

    NFS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 239

    Checking

    the

    status

    of

    DB2

    and

    SAP

    connections

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 240

    Availability

    test

    scenarios

    .

    .

    .

    .

    .

    .

    .

    .

    . 241

    Chapter

    13.

    Verification

    and

    problem

    determination

    on

    Linux

    for

    zSeries

    .

    . 243

    Verification

    procedure

    and

    failover

    scenarios

    .

    .

    . 243

    Test

    setup

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 243

    Scenarios

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 243

    Part

    6.

    Appendixes

    .

    .

    .

    .

    .

    .

    .

    . 247

    Appendix

    A.

    Network

    setup

    .

    .

    .

    .

    . 249

    Network

    hardware

    components

    for

    the

    test

    setup

    249

    Networking

    software

    components

    for

    the

    test

    setup

    250

    z/OS

    network

    settings

    for

    the

    test

    setup

    .

    .

    . 250

    Linux

    for

    zSeries

    network

    settings

    for

    the

    test

    setup

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 254

    AIX

    OSPF

    definitions

    for

    the

    ’gated’

    daemon

    255

    Domain

    Name

    Server

    (DNS)

    definitions

    .

    .

    . 256

    Appendix

    B.

    File

    system

    setup

    .

    .

    .

    . 257

    NFS

    server

    procedure

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 257

    NFS

    export

    file

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 257

    NFS

    attribute

    file

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 257

    Mount

    commands

    on

    Linux

    /etc/fstab

    .

    .

    .

    .

    . 258

    Appendix

    C.

    ARM

    policy

    .

    .

    .

    .

    .

    .

    . 259

    ARM

    policy

    JCL

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 259

    Appendix

    D.

    Basic

    setup

    of

    Tivoli

    NetView

    and

    Tivoli

    System

    Automation

    for

    z/OS

    .

    .

    .

    .

    .

    .

    .

    . 261

    Status

    Display

    Facility

    definition

    .

    .

    .

    .

    .

    .

    . 261

    AOFPSYST

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 261

    AOFSAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 263

    AOFTSC04

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 265

    Sample

    REXX

    procedure

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 267

    SANCHK

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 267

    Appendix

    E.

    Detailed

    description

    of

    the

    z/OS

    high

    availability

    scripts

    .

    .

    . 271

    Script

    availability

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 271

    Script

    descriptions

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 272

    Introduction

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 272

    startappsrv_v4

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 274

    stopappsrv_v4

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 276

    checkappsrv_v4

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 277

    startsap_em00

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 278

    Appendix

    F.

    Detailed

    description

    of

    the

    Tivoli

    System

    Automation

    for

    Linux

    high

    availability

    policy

    for

    SAP

    . 281

    Contents

    v

  • The

    ENQ

    group

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 281

    The

    ENQREP

    group

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 281

    The

    application

    server

    groups

    .

    .

    .

    .

    .

    .

    .

    . 281

    The

    SAP

    router

    group

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 282

    Interaction

    between

    ES

    and

    ERS

    .

    .

    .

    .

    .

    .

    . 282

    Creating

    the

    resources

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 283

    The

    SAP

    processes

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 283

    Creating

    the

    resource

    groups

    .

    .

    .

    .

    .

    .

    .

    . 287

    Setup

    scripts

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 289

    Specifying

    the

    configuration

    (saphasalinux.conf)

    289

    Setting

    up

    the

    policy

    (mksap)

    .

    .

    .

    .

    .

    .

    . 290

    Cleaning

    up

    the

    policy

    (rmsap)

    .

    .

    .

    .

    .

    . 291

    Monitoring

    the

    status

    of

    the

    policy

    (lssap)

    .

    .

    . 291

    Automation

    scripts

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 292

    Monitoring

    or

    stopping

    a

    Linux

    process

    (sapctrl_pid)

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 292

    Managing

    SCS

    (sapctrl_em)

    .

    .

    .

    .

    .

    .

    . 293

    Managing

    the

    application

    server

    instances

    (sapctrl_as)

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 295

    Managing

    SAPSID-independent

    resources

    (sapctrl_sys)

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 297

    List

    of

    abbreviations

    .

    .

    .

    .

    .

    .

    .

    . 299

    Glossary

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 305

    Bibliography

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 311

    IBM

    documents

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 311

    SAP

    documents

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 314

    SAP

    Notes

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 314

    APARs

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 315

    Notices

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 317

    Trademarks

    and

    service

    marks

    .

    .

    .

    .

    .

    .

    . 317

    Index

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 321

    vi

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • Figures

    1.

    The

    concept

    of

    autonomic

    computing

    xviii

    2.

    Causes

    of

    application

    downtime

    and

    appropriate

    response

    .

    .

    .

    .

    .

    .

    .

    .

    . xxi

    3.

    The

    closed

    loop

    of

    automation

    .

    .

    .

    .

    .

    . xxii

    4.

    zSeries

    Parallel

    Sysplex

    architecture

    elements

    18

    5.

    DB2

    data

    sharing

    in

    a

    Parallel

    Sysplex

    .

    .

    . 19

    6.

    SAP

    sysplex

    failover

    configuration:

    Option

    0

    example

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 20

    7.

    Option

    0:

    Single

    DB2

    member

    with

    passive

    (inactive)

    standby

    member

    .

    .

    .

    .

    .

    .

    . 24

    8.

    Option

    1:

    Two

    active

    DB2

    members

    without

    passive

    standby

    members

    .

    .

    .

    .

    .

    .

    .

    . 25

    9.

    Large

    company

    using

    architecture

    options

    0

    and

    1

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 28

    10.

    Option

    2:

    Two

    active

    DB2

    members,

    each

    with

    a

    passive

    standby

    member

    in

    the

    same

    LPAR

    . 30

    11.

    Option

    3:

    Two

    active

    DB2

    members,

    each

    with

    a

    passive

    standby

    member

    in

    an

    independent

    LPAR

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 31

    12.

    Database

    recovery

    in

    a

    data

    sharing

    group

    40

    13.

    Example

    of

    high

    availability

    with

    GDPS

    configuration

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 56

    14.

    Process

    for

    obtaining

    a

    non-disruptive

    volume

    backup

    without

    the

    BACKUP

    SYSTEM

    utility

    of

    DB2

    V8

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 57

    15.

    Sample

    VSWITCH

    utilization

    .

    .

    .

    .

    .

    . 68

    16.

    SAP

    sysplex

    failover

    configuration:

    Option

    0

    example

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 69

    17.

    VIPA

    and

    OSPF

    recovery

    mechanisms

    under

    z/OS

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 72

    18.

    Recommended

    setup

    for

    a

    high

    availability

    network

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 75

    19.

    System

    setup

    with

    z/OS

    ARP

    takeover

    and

    Windows

    adapter

    teaming

    .

    .

    .

    .

    .

    .

    . 77

    20.

    SAP

    enqueue

    services

    with

    the

    old

    central

    instance

    concept

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 91

    21.

    Initial

    startup

    of

    SCS

    .

    .

    .

    .

    .

    .

    .

    .

    . 93

    22.

    Failure

    of

    SCS

    and

    recovery

    of

    the

    enqueue

    table

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 94

    23.

    Movement

    of

    the

    enqueue

    replication

    server

    94

    24.

    General

    concept

    of

    a

    fault-tolerant

    network

    95

    25.

    Alternative

    paths

    in

    a

    duplicated

    network

    96

    26.

    Rerouting

    if

    a

    network

    adapter

    card

    fails

    97

    27.

    Rerouting

    in

    a

    sysplex

    even

    in

    case

    of

    two

    failing

    network

    cards

    .

    .

    .

    .

    .

    .

    .

    .

    . 97

    28.

    VIPA

    takeover

    and

    dynamic

    routing

    .

    .

    .

    . 98

    29.

    Initial

    NFS

    client/server

    configuration

    101

    30.

    Failover

    of

    the

    NFS

    server

    .

    .

    .

    .

    .

    .

    . 101

    31.

    Application

    servers

    connected

    to

    primary

    and

    standby

    database

    servers

    .

    .

    .

    .

    .

    .

    .

    . 104

    32.

    Failover

    setup

    using

    DB2

    Connect,

    with

    multiple

    DB2

    members

    in

    the

    same

    LPAR

    .

    . 105

    33.

    High

    availability

    solution

    configuration

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 114

    34.

    Directory

    tree

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 120

    35.

    Defining

    the

    gateway

    host

    for

    rfcoscol

    with

    transaction

    SM59

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 136

    36.

    RED_DB2PLEX

    application

    group

    .

    .

    .

    .

    . 158

    37.

    RED_EMPLEX

    and

    RED_ERSPLEX

    application

    groups

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 164

    38.

    RED_VPLEX

    application

    group

    .

    .

    .

    .

    . 165

    39.

    RED_COPLEX

    application

    group

    .

    .

    .

    .

    . 166

    40.

    RED_RASPLEX

    application

    group

    .

    .

    .

    . 170

    41.

    RED_LASPLEX

    application

    group

    .

    .

    .

    .

    . 171

    42.

    RED_LOCAL

    application

    group

    .

    .

    .

    .

    . 173

    43.

    NFS_HAPLEX

    application

    group

    .

    .

    .

    .

    . 174

    44.

    SAP_RTPLEX

    application

    group

    .

    .

    .

    .

    . 176

    45.

    SAP_LOCAL

    application

    group

    .

    .

    .

    .

    . 178

    46.

    RED_SAPPLEX

    application

    group

    .

    .

    .

    .

    . 179

    47.

    SAP

    application

    group

    .

    .

    .

    .

    .

    .

    .

    . 180

    48.

    Overview

    of

    the

    resources

    .

    .

    .

    .

    .

    .

    . 181

    49.

    SMB_PLEX

    application

    group

    .

    .

    .

    .

    .

    . 185

    50.

    Overview

    of

    the

    SAP

    policy

    definitions

    189

    51.

    SM12

    primary

    panel

    .

    .

    .

    .

    .

    .

    .

    .

    . 207

    52.

    Error

    handling

    menu

    .

    .

    .

    .

    .

    .

    .

    .

    . 208

    53.

    Enqueue

    test:

    start

    mass

    enqueue

    operations

    208

    54.

    List

    of

    entries

    in

    the

    enqueue

    table

    .

    .

    .

    . 209

    55.

    SAP

    system

    log

    (SM21)

    .

    .

    .

    .

    .

    .

    .

    . 219

    56.

    SAP

    system

    log

    (SM21)

    .

    .

    .

    .

    .

    .

    .

    . 221

    57.

    SAP

    system

    log

    (SM21)

    .

    .

    .

    .

    .

    .

    .

    . 223

    58.

    Results

    of

    SDSF

    DA

    command

    .

    .

    .

    .

    .

    . 240

    59.

    Results

    of

    DB2

    Display

    Thread

    command

    241

    60.

    Networking

    configuration

    for

    the

    high

    availability

    solution

    for

    SAP

    .

    .

    .

    .

    .

    . 249

    ©

    Copyright

    IBM

    Corp.

    2004

    vii

  • viii

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • Tables

    1.

    Selected

    zSeries

    availability

    features

    matrix

    3

    2.

    Parallel

    Sysplex

    availability

    features

    matrix

    6

    3.

    DB2

    UDB

    for

    z/OS

    availability

    features

    matrix

    8

    4.

    Large

    company

    using

    architecture

    option

    2

    34

    5.

    Recovery

    attributes

    of

    the

    recommended

    setup

    76

    6.

    Retransmission

    intervals

    .

    .

    .

    .

    .

    .

    .

    . 80

    7.

    Possible

    ICLI_TCP_KEEPALIVE

    values

    85

    8.

    Simple

    configuration

    .

    .

    .

    .

    .

    .

    .

    .

    . 106

    9.

    DB2

    sysplex

    data

    sharing

    configuration

    with

    double

    network

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 108

    10.

    Fully

    implemented

    high

    availability

    solution

    for

    SAP

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 110

    11.

    Software

    requirements

    for

    the

    HA

    solution

    114

    12.

    SAP

    application

    server

    for

    Linux

    for

    zSeries

    115

    13.

    Recommended

    names

    for

    all

    z/OS-related

    components

    of

    an

    SAP

    system

    .

    .

    .

    .

    .

    . 116

    14.

    Recommended

    names

    for

    all

    components

    of

    an

    individual

    SAP

    system

    .

    .

    .

    .

    .

    .

    . 117

    15.

    Naming

    conventions

    for

    SA

    for

    z/OS

    resources

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 117

    16.

    SAP

    profile

    parameters

    relevant

    for

    the

    high

    availability

    solution

    .

    .

    .

    .

    .

    .

    .

    .

    . 127

    17.

    Summary

    of

    start/stop

    monitoring

    commands

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 137

    18.

    Summary

    of

    the

    classes

    .

    .

    .

    .

    .

    .

    .

    . 181

    19.

    Summary

    of

    the

    applications

    .

    .

    .

    .

    .

    . 181

    20.

    Summary

    of

    the

    application

    groups

    .

    .

    .

    . 182

    21.

    Examples

    of

    test

    scenarios

    .

    .

    .

    .

    .

    .

    . 201

    22.

    Stop

    of

    the

    entire

    SAP

    system

    with

    SA

    OS/390

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 211

    23.

    Start

    of

    the

    entire

    SAP

    system

    with

    SA

    OS/390

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 211

    24.

    Startup

    of

    the

    first

    LPAR

    .

    .

    .

    .

    .

    .

    .

    . 212

    25.

    Startup

    of

    the

    second

    LPAR

    .

    .

    .

    .

    .

    .

    . 213

    26.

    Shutdown

    of

    the

    LPAR

    where

    the

    ES

    and

    NFS

    servers

    are

    running

    .

    .

    .

    .

    .

    .

    .

    . 213

    27.

    Restart

    of

    the

    LPAR

    where

    the

    ES

    and

    NFS

    servers

    are

    running

    .

    .

    .

    .

    .

    .

    .

    .

    . 214

    28.

    Failure

    of

    the

    enqueue

    server

    .

    .

    .

    .

    .

    . 217

    29.

    Failure

    of

    the

    message

    server

    .

    .

    .

    .

    .

    . 220

    30.

    Failure

    of

    the

    ICLI

    server

    .

    .

    .

    .

    .

    .

    . 221

    31.

    Failure

    of

    the

    NFS

    server

    .

    .

    .

    .

    .

    .

    . 224

    32.

    Failure

    of

    a

    TCP/IP

    stack

    .

    .

    .

    .

    .

    .

    . 225

    33.

    Failure

    of

    the

    LPAR

    where

    the

    ES

    and

    NFS

    servers

    are

    running

    .

    .

    .

    .

    .

    .

    .

    .

    . 228

    34.

    High

    availability

    test

    scenarios

    .

    .

    .

    .

    .

    . 241

    35.

    Planned

    Outages

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 243

    36.

    Unplanned

    Outages

    .

    .

    .

    .

    .

    .

    .

    .

    . 245

    37.

    List

    of

    IBM

    Collection

    Kits

    .

    .

    .

    .

    .

    .

    . 311

    38.

    IBM

    DB2

    documents

    .

    .

    .

    .

    .

    .

    .

    .

    . 311

    39.

    IBM

    z/OS

    documents

    .

    .

    .

    .

    .

    .

    .

    .

    . 312

    40.

    Other

    IBM

    reference

    documents

    .

    .

    .

    .

    . 312

    41.

    IBM

    Redbooks

    and

    Redpapers

    covering

    related

    topics

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 313

    42.

    IBM

    order

    numbers

    and

    SAP

    material

    numbers

    for

    editions

    of

    the

    IBM

    Planning

    Guide

    and

    Connectivity

    Guide

    .

    .

    .

    .

    .

    . 314

    43.

    SAP

    documents

    .

    .

    .

    .

    .

    .

    .

    .

    .

    .

    . 314

    ©

    Copyright

    IBM

    Corp.

    2004

    ix

  • x

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • About

    this

    document

    This

    book

    describes

    the

    IBM

    High

    Availability

    Solution

    for

    SAP,

    which

    provides

    the

    means

    for

    fully

    automating

    the

    management

    of

    all

    SAP

    components

    and

    related

    products

    running

    on

    z/OS,

    AIX,

    Windows,

    or

    Linux.

    The

    automation

    software

    monitors

    all

    resources

    and

    controls

    the

    restart

    and/or

    takeover

    of

    failing

    components,

    thereby

    ensuring

    near

    continuous

    availability

    of

    the

    SAP

    system.

    Major

    portions

    of

    this

    book

    were

    derived

    from

    the

    following

    publications

    by

    the

    IBM

    International

    Technical

    Support

    Organization:

    v

    SAP

    R/3

    on

    DB2

    UDB

    for

    OS/390:

    Database

    Availability

    Considerations,

    SG24-5690

    v

    SAP

    on

    DB2

    UDB

    for

    OS/390

    and

    z/OS:

    High

    Availability

    Solution

    Using

    System

    Automation,

    SG24-6836

    v

    SAP

    on

    DB2

    for

    z/OS

    and

    OS/390:

    High

    Availability

    and

    Performance

    Monitoring

    with

    Data

    Sharing,

    SG24-6950

    v

    mySAP

    Business

    Suite

    Managed

    by

    IBM

    Tivoli

    System

    Automation

    for

    Linux,

    REDP-3717

    The

    original

    documents

    are

    available

    at:

    http://www.redbooks.ibm.com

    Who

    should

    read

    this

    document

    This

    document

    is

    intended

    for

    system

    and

    database

    administrators

    who

    need

    to

    support

    SAP

    systems

    that

    must

    offer

    a

    high

    level

    of

    availability.

    Important

    remarks

    As

    of

    SAP

    Web

    Application

    Server

    6.40,

    the

    functions

    of

    the

    Integrated

    Call

    Level

    Interface

    (ICLI)

    component

    of

    z/OS,

    which

    was

    used

    in

    previous

    SAP

    database

    releases

    for

    remote

    SQL

    interface

    between

    clients

    and

    the

    DB2

    database

    server,

    have

    been

    replaced

    by

    the

    IBM

    DB2

    Connect

    product.

    Unless

    otherwise

    stated,

    for

    SAP

    Web

    Application

    Server

    6.40

    and

    above,

    references

    in

    this

    document

    to

    the

    term

    ICLI

    server

    should

    be

    understood

    as

    applying

    to

    DDF

    (DB2’s

    Distributed

    Data

    Facility)

    for

    SAP

    NetWeaver

    ’04,

    and

    references

    to

    the

    ICLI

    client

    should

    be

    understood

    as

    applying

    to

    DB2

    Connect.

    The

    described

    configuration

    applies

    to

    SAP

    R/3

    4.6

    and

    SAP

    Web

    Application

    Server

    6.20.

    The

    concept

    applies

    to

    higher

    SAP

    releases

    as

    well,

    although

    policies

    and

    scripts

    will

    need

    to

    be

    adapted.

    Conventions

    and

    terminology

    used

    in

    this

    document

    In

    this

    document,

    the

    following

    naming

    conventions

    apply:

    v

    IBM

    DB2

    Universal

    Database

    for

    z/OS

    (or

    OS/390)

    is

    usually

    referred

    to

    as

    DB2.

    v

    The

    SAP

    on

    DB2

    UDB

    for

    OS/390

    and

    z/OS

    system

    is

    usually

    referred

    to

    as

    SAP

    on

    DB2.

    v

    The

    term

    ″UNIX″

    stands

    for

    AIX

    and

    z/OS

    UNIX

    System

    Services.

    ″UNIX(-like)″

    or

    ″UNIX(-style)″

    refers

    to

    UNIX

    and

    Linux.

    v

    AIX

    5.x

    (64-bit)

    is

    usually

    referred

    to

    as

    AIX.

    v

    Linux

    for

    zSeries

    (64-bit)

    is

    usually

    referred

    to

    as

    Linux.

    ©

    Copyright

    IBM

    Corp.

    2004

    xi

    http://www.redbooks.ibm.com

  • v

    The

    term

    ″Windows″

    is

    used

    to

    encompass

    Windows

    2000

    and

    its

    supported–

    successors

    (32-bit

    version).

    v

    The

    term

    ″currently″

    refers

    to

    this

    document’s

    edition

    date.

    v

    The

    term

    ″SAP

    installation

    tool″

    refers

    to

    the

    current

    SAP

    installation

    utility

    (see

    SAP

    Web

    Application

    Server

    Installation

    on

    UNIX:

    IBM

    DB2

    UDB

    for

    OS/390

    and

    z/OS).

    v

    The

    IBM

    products

    Tivoli

    System

    Automation

    for

    z/OS

    (formerly

    System

    Automation

    for

    OS/390,

    or

    SA

    OS/390)

    and

    Tivoli

    System

    Automation

    for

    Multiplatforms

    (formerly

    Tivoli

    System

    Automation

    for

    Linux,

    or

    SA

    for

    Linux)

    are

    referred

    to

    collectively

    in

    this

    document

    as

    Tivoli

    System

    Automation

    (TSA).

    When

    it

    is

    appropriate

    to

    distinguish

    between

    the

    supported

    operating

    system

    platforms,

    SA

    for

    z/OS

    and

    SA

    for

    Linux

    are

    also

    employed.

    SA

    for

    Linux

    designates

    Tivoli

    System

    Automation

    for

    Linux

    V1.1.3.1,

    which

    is

    the

    minimum

    required

    level

    for

    the

    high

    availability

    solution

    described

    in

    this

    document.

    v

    The

    term

    NetView

    refers

    to

    the

    IBM

    products

    Tivoli

    NetView

    for

    OS/390

    and

    its

    successor,

    Tivoli

    NetView

    for

    z/OS.

    v

    DB2

    documentation

    is

    usually

    cited

    in

    the

    text

    without

    a

    specific

    release

    or

    order

    number,

    since

    these

    numbers

    are

    different

    for

    DB2

    V8.

    Refer

    to

    “Bibliography”

    on

    page

    311

    for

    specific

    information.

    v

    The

    term

    Planning

    Guide

    encompasses

    three

    separate

    documents:

    IBM

    document

    SAP

    R/3

    on

    DB2

    for

    OS/390:

    Planning

    Guide,

    2nd

    Edition,

    SAP

    R/3

    Release

    4.6D

    for

    supported

    versions

    of

    SAP

    R/3

    IBM

    document

    SAP

    on

    DB2

    for

    OS/390

    and

    z/OS:

    Planning

    Guide,

    2nd

    Edition,

    SAP

    Web

    Application

    Server

    6.20

    for

    SAP

    Web

    Application

    server

    versions

    up

    to

    and

    including

    6.20

    (including

    use

    of

    the

    6.40

    downward-compatible

    kernel

    with

    release

    6.20),

    with

    ICLI

    as

    the

    remote

    SQL

    interface

    SAP

    document

    Planning

    Guide:

    z/OS

    Configuration

    for

    SAP

    on

    IBM

    DB2

    Universal

    Database

    for

    z/OS,

    applying

    to

    SAP

    Web

    Application

    server

    version

    6.40

    (SAP

    NetWeaver

    ’04)

    and

    higher,

    which

    requires

    DB2

    UDB

    Version

    8

    and

    DB2

    Connect

    as

    a

    replacement

    for

    ICLI.

    Unless

    otherwise

    stated,

    the

    term

    Planning

    Guide

    refers

    to

    the

    version

    for

    the

    system

    under

    discussion.

    To

    ensure

    clarity,

    the

    abbreviations

    4.6D

    Planning

    Guide,

    6.20

    Planning

    Guide,

    and

    6.40

    Planning

    Guide

    are

    also

    used.

    Full

    titles

    and

    numbers

    for

    these

    publications

    are

    provided

    in

    the

    bibliography.

    v

    The

    IBM

    documentation

    SAP

    R/3

    on

    DB2

    UDB

    for

    OS/390

    and

    z/OS:

    Connectivity

    Guide,

    4th

    Edition

    is

    usually

    referred

    to

    as

    the

    Connectivity

    Guide..

    v

    The

    SAP

    documentation

    SAP

    on

    IBM

    DB2

    UDB

    for

    OS/390

    and

    z/OS:

    Database

    Administration

    Guide:

    SAP

    Web

    Application

    Server

    is

    usually

    referred

    to

    as

    the

    SAP

    Database

    Administration

    Guide.

    This

    is

    not

    to

    be

    confused

    with

    the

    IBM

    DB2

    Administration

    Guide

    publication.

    v

    The

    term

    SAP

    installation

    guides

    refers

    to

    the

    following

    SAP

    documentation:

    SAP

    Web

    Application

    Server

    Installation

    on

    UNIX:

    IBM

    DB2

    UDB

    for

    OS/390

    and

    z/OS

    SAP

    Web

    Application

    Server

    Installation

    on

    Windows:

    IBM

    DB2

    UDB

    for

    OS/390

    and

    z/OS

    SAP

    NetWeaver

    ’04

    Installation

    Guide:

    SAP

    Web

    Application

    Server

    ABAP

    6.40

    on

    UNIX:

    IBM

    DB2

    UDB

    for

    z/OS

    SAP

    NetWeaver

    ’04

    Installation

    Guide:

    SAP

    Web

    Application

    Server

    ABAP

    6.40

    on

    Windows:

    IBM

    DB2

    UDB

    for

    z/OS

    xii

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • Highlighting

    conventions

    Italics

    are

    used

    for:

    v

    document

    titles

    v

    emphasis

    v

    options,

    variables

    and

    parameters

    Boldface

    is

    used

    for:

    v

    check

    box

    labels

    v

    choices

    in

    menus

    v

    column

    headings

    v

    entry

    fields

    v

    field

    names

    in

    windows

    v

    menu-bar

    choices

    v

    menu

    names

    v

    radio

    button

    names

    v

    spin

    button

    names

    Monospace

    is

    used

    for:

    v

    coding

    examples

    v

    commands

    and

    subcommands

    v

    entered

    data

    v

    file

    names

    v

    group

    and

    user

    IDs

    v

    message

    text

    v

    path

    names

    Underlined

    settings

    are:

    v

    default

    values

    Bold

    italics

    are

    used

    for:

    v

    recommended

    values

    Syntax

    diagrams

    This

    document

    uses

    railroad

    syntax

    diagrams

    to

    illustrate

    how

    to

    use

    commands.

    This

    is

    how

    you

    read

    a

    syntax

    diagram:

    A

    command

    or

    keyword

    that

    you

    must

    enter

    (a

    required

    command)

    is

    displayed

    like

    this:

    ��

    Command

    ��

    An

    optional

    keyword

    is

    shown

    below

    the

    line,

    like

    this:

    ��

    Option

    ��

    A

    default

    is

    shown

    over

    the

    line,

    like

    this:

    ��

    Default

    ��

    About

    this

    document

    xiii

  • An

    item

    that

    can

    be

    repeated

    (meaning

    that

    more

    than

    one

    optional

    keyword

    can

    be

    called)

    is

    shown

    like

    this:

    ��

    Repeat

    ��

    Prerequisite

    and

    related

    information

    SAP

    on

    DB2

    uses

    a

    variety

    of

    different

    hardware

    and

    software

    systems.

    This

    document

    concentrates

    on

    information

    that

    goes

    beyond

    the

    standard

    knowledge

    needed

    for

    DB2

    and

    SAP

    system

    administration.

    Therefore,

    it

    is

    assumed

    that

    you

    are

    familiar

    with:

    v

    The

    z/OS

    environment

    (TSO,

    z/OS,

    UNIX

    System

    Services,

    RACF,

    JCL,

    RMF,

    WLM)

    v

    DB2

    administration

    (for

    example,

    SQL,

    SPUFI,

    and

    the

    utilities

    REORG

    and

    RUNSTATS)

    v

    AIX,

    Linux

    for

    z/Series,

    or

    Windows

    (or

    all)

    Refer

    to

    “Bibliography”

    on

    page

    311

    for

    a

    list

    of

    related

    documentation.

    Additional

    information

    is

    available

    from

    SAP

    as

    part

    of

    the

    help

    system:

    http://help.sap.com

    How

    to

    send

    in

    your

    comments

    Your

    feedback

    is

    important

    in

    helping

    to

    provide

    the

    most

    accurate

    and

    high-quality

    information.

    If

    you

    have

    any

    comments

    about

    this

    document

    or

    any

    other

    z/OS

    documentation:

    v

    Visit

    our

    home

    page

    at

    http://www.ibm.com/servers/eserver/zseries/software/sap

    Click

    on

    ″Contact″

    at

    the

    bottom

    of

    the

    page.

    v

    Send

    your

    comments

    by

    e-mail

    to

    [email protected].

    Be

    sure

    to

    include

    the

    document’s

    name

    and

    part

    number,

    the

    version

    of

    z/OS,

    and,

    if

    applicable,

    the

    specific

    location

    of

    the

    passage

    you

    are

    commenting

    on

    (for

    example,

    a

    page

    number

    or

    table

    number).

    v

    Fill

    out

    one

    of

    the

    forms

    at

    the

    back

    of

    this

    document

    and

    return

    it

    by

    mail,

    by

    fax,

    or

    by

    giving

    it

    to

    an

    IBM

    representative.

    Content

    of

    this

    document

    This

    document

    describes

    the

    activities

    that

    need

    to

    be

    completed

    before

    the

    actual

    SAP

    installation

    via

    the

    SAP

    system

    installation

    tool

    can

    be

    started,

    and

    administrative

    tasks

    that

    may

    have

    to

    be

    performed

    repeatedly

    during

    the

    lifetime

    of

    the

    system.

    Chapter

    descriptions

    follow

    below:

    “Introducing

    high

    availability

    and

    automation

    for

    SAP”

    on

    page

    xvii

    Provides

    general

    information

    on

    high

    availability

    in

    an

    SAP

    environment.

    Part

    1,

    “Database

    considerations

    for

    high

    availability,”

    on

    page

    1

    xiv

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

    http://help.sap.comhttp://www.ibm.com/servers/eserver/zseries/software/sap

  • This

    part

    lists

    the

    availability

    benefits

    provided

    by

    the

    zSeries

    hardware,

    z/OS,

    and

    DB2,

    discusses

    DB2

    data

    sharing,

    identifies

    architecture

    options,

    and

    describes

    backup

    and

    recovery

    in

    a

    data

    sharing

    environment.

    Part

    2,

    “Network

    considerations

    for

    high

    availability,”

    on

    page

    63

    Describes

    a

    highly-available

    network

    established

    for

    testing

    and

    makes

    general

    recommendations

    concerning

    network

    setup.

    It

    also

    discusses

    the

    implementation

    of

    a

    high

    availability

    solution

    as

    it

    affects

    the

    client/server

    configuration

    and

    addresses

    timeout

    considerations.

    Part

    3,

    “Application

    server

    considerations

    for

    high

    availability,”

    on

    page

    87

    This

    part

    discusses

    the

    components

    of

    the

    architecture,

    including

    considerations

    for

    SAP

    Central

    Services

    (SCS),

    network,

    file

    system,

    database,

    information

    on

    remote

    application

    servers

    and

    sysplex

    failover

    support.

    It

    offers

    scenarios

    showing

    different

    high

    availability

    implementations

    and

    also

    gives

    information

    on

    planning

    for

    high

    availability

    implementation,

    with

    considerations

    for

    DB2,

    network,

    file

    system,

    Tivoli

    System

    Automation,

    and

    SAP

    installation.

    It

    then

    describes

    what

    is

    needed

    to

    adapt

    the

    SAP

    system

    to

    the

    high

    availability

    solution,

    including

    configuring

    SAP

    for

    SCS

    and

    for

    Tivoli

    System

    Automation.

    Finally,

    it

    discusses

    issues

    in

    updating

    and

    upgrading

    the

    system

    components.

    Part

    4,

    “Autonomic

    operation

    of

    the

    high

    availability

    solution

    for

    SAP,”

    on

    page

    149

    Discusses

    the

    customization

    of

    SA

    for

    z/OS

    and

    SA

    for

    Linux.

    Part

    5,

    “Verification

    and

    problem

    determination,”

    on

    page

    199

    Addresses

    how

    to

    confirm

    that

    the

    high-availability

    implementation

    is

    correct

    on

    z/OS

    and

    Linux,

    and,

    if

    not,

    how

    to

    determine

    where

    the

    problems

    lie

    and

    how

    to

    resolve

    them.

    ″Appendixes″

    Provide

    setup

    details

    for

    networking,

    file

    systems,

    Automatic

    Restart

    Management,

    NetView,

    and

    Tivoli

    System

    Automation.

    Also

    available

    are

    a

    detailed

    description

    of

    the

    scripts

    that

    support

    high

    availability

    on

    z/OS

    and

    how

    to

    obtain

    updates,

    and

    details

    of

    the

    high

    availability

    policy

    for

    SAP

    used

    with

    SA

    for

    Linux.

    “List

    of

    abbreviations”

    on

    page

    299

    Contains

    a

    list

    of

    important

    abbreviations

    appearing

    in

    this

    document.

    “Glossary”

    on

    page

    305

    Explains

    the

    meaning

    of

    the

    most

    important

    technical

    terms

    employed

    in

    this

    document.

    “Bibliography”

    on

    page

    311

    Contains

    lists

    of

    the

    IBM

    and

    SAP

    documentation

    referred

    to

    elsewhere

    in

    this

    document,

    including

    SAP

    Notes

    and

    APARs.

    About

    this

    document

    xv

  • xvi

    High

    Availability

    for

    SAP

    on

    zSeries

    Using

    Autonomic

    Computing

    Technologies

    (September

    14,

    2004)

  • Introducing

    high

    availability

    and

    automation

    for

    SAP

    The

    solution

    documented

    in

    this

    book

    uses

    autonomic

    computing

    technologies

    of

    IBM

    eServer

    products

    to

    provide

    automation

    and

    high

    availability

    for

    SAP

    systems.

    The

    availability

    of

    a

    production

    SAP

    system

    is

    a

    critical

    business

    factor

    and

    therefore

    requires

    the

    highest

    level

    of

    availability.

    Continuous

    availability

    combines

    the

    characteristics

    of

    high

    availability

    (the

    ability

    to

    avoid

    unplanned

    outages

    by

    eliminating

    single

    points

    of

    failure)

    and

    continuous

    operation

    (the

    ability

    to

    avoid

    planned

    outages,

    such

    as

    for

    administrative

    or

    maintenance

    work)

    in

    order

    to

    keep

    the

    SAP

    system

    running

    as

    close

    to

    24x365

    as

    possible.

    IBM

    eServer

    products

    incorporate

    a

    variety

    of

    advanced

    autonomic

    computing

    capabilities

    based

    on

    the

    four

    characteristics

    of

    self-managing

    systems:

    Self-configuring

    The

    seamless

    integration

    of

    new

    hardware

    resources

    and

    the

    cooperative

    yielding

    of

    resources

    by

    the

    operating

    system

    is

    an

    important

    element

    of

    self-configuring

    systems.

    Hardware

    subsystems

    and

    resources

    can

    configure

    and

    re-configure

    autonomously

    both

    at

    boot

    time

    and

    during

    run

    time.

    This

    action

    can

    be

    initiated

    by

    the

    need

    to

    adjust

    the

    allocation

    of

    resources

    based

    on

    the

    current

    optimization

    criteria

    or

    in

    response

    to

    hardware

    or

    firmware

    faults.

    Self-configuring

    also

    includes

    the

    ability

    to

    concurrently

    add

    or

    remove

    hardware

    resources

    in

    response

    to

    commands

    from

    administrators,

    service

    personnel,

    or

    hardware

    resource

    management

    software.

    Self-healing

    With

    self-healing

    capabilities,

    platforms

    can

    detect

    hardware

    and

    firmware

    faults

    instantly

    and

    then

    contain

    the

    effects

    of

    the

    faults

    within

    defined

    boundaries.

    This

    allows

    platforms

    to

    recover

    from

    the

    negative

    effects

    of

    such

    faults

    with

    minimal

    or

    no

    impact

    on

    the

    execution

    of

    operating

    system

    and

    user-level

    workloads.

    Self-optimizing

    Self-optimizing

    capabilities

    allow

    computing

    systems

    to

    autonomously

    measure

    the

    performance

    or

    usage

    of

    resources

    and

    then

    tune

    the

    configuration

    of

    hardware

    resources

    to

    deliver

    improved

    performance.

    Self-protecting

    This

    allows

    computing

    systems

    to

    protect

    against

    internal

    and

    external

    threats

    to

    the

    integrity

    and

    privacy

    of

    applications

    and

    data.

    These

    four

    components

    are

    illustrated

    in

    the

    following

    graphic:

    ©

    Copyright

    IBM

    Corp.

    2004

    xvii

  • Since

    the

    initial

    announcement

    of

    SAP

    on

    DB2

    UDB

    for

    OS/390

    and

    z/OS1

    ,we

    have

    used

    DB2

    Parallel

    Sysplex

    data

    sharing

    combined

    with

    the

    SAP

    sysplex

    failover

    feature

    to

    remove

    the

    database

    server

    as

    a

    single

    point

    of

    failure.

    This

    also

    gave

    customers

    the

    ability

    to

    avoid

    planned

    and

    unplanned

    outages

    of

    the

    database

    server.

    See

    “Remote

    application

    server

    and

    sysplex

    failover

    support”

    on

    page

    103.

    The

    high

    availability

    solution

    presented

    in

    this

    book

    further

    enhances

    this

    capability

    by

    removing

    the

    SAP

    central

    instance

    as

    a

    single

    point

    of

    failure

    and

    providing

    a

    means

    to

    automate

    the

    management

    of

    all

    SAP

    components

    for

    planned

    and

    unplanned

    outages.

    This

    is

    achieved

    by

    combining

    the

    concepts

    of

    system

    automation

    and

    transparent

    failover

    in

    a

    Parallel

    Sysplex.

    Based

    on

    the

    IBM

    product

    Tivoli

    System

    Automation

    (TSA),

    together

    with

    a

    redesign

    of

    the

    SAP

    central

    instance

    concept,

    this

    high

    availability

    solution

    exploits

    the

    new

    SAP

    standalone

    enqueue

    server,

    the

    enqueue

    replication

    server,

    dynamic

    virtual

    IP

    addresses

    (VIPA

    ),

    shared

    file

    system,

    and

    DB2

    data

    sharing

    to

    guarantee

    a

    minimum

    of

    SAP

    system

    outages

    along

    with

    a

    maximum

    of

    automation.

    The

    implementation

    and

    customization

    of

    the

    complete

    HA

    solution

    highly

    depends

    on

    the

    customer

    configuration

    and

    requires

    TSA

    skill.

    We

    strongly

    recommend

    that

    customers

    request

    support

    from

    IBM

    Global

    Services.

    Before

    going

    live,

    customers

    should

    also

    contact

    SAP

    for

    a

    final

    check

    of

    the

    setup.

    The

    high

    availability

    solution

    for

    SAP

    provides

    the

    means

    for

    fully

    automating

    the

    management

    of

    all

    SAP

    components

    and

    related

    products

    running

    on

    z/OS,

    AIX,

    Windows,

    or

    Linux.

    The

    automation

    software

    monitors

    all

    resources

    and

    controls

    the

    restart

    and/or

    takeover

    of

    failing

    components,

    thereby

    ensuring

    near

    continuous

    availability

    of

    the

    SAP

    system.

    The

    availability

    of

    the

    enqueue

    server

    is

    extremely

    critical

    for

    an

    SAP

    system.

    If

    it

    fails,

    most

    SAP

    transactions

    will

    also

    fail.

    To

    address

    this

    single

    point

    of

    failure,

    SAP,

    in

    close

    cooperation

    with

    IBM,

    has

    changed

    the

    architecture

    of

    the

    enqueue

    server.

    It

    is

    no

    longer

    part

    of

    the

    so-called

    “central

    instance”.

    That

    is,

    it

    no

    longer

    runs

    inside

    a

    work

    process,

    but

    is

    now

    a

    standalone

    process

    called

    the

    standalone

    enqueue

    server

    (which

    operates

    under

    the

    designation

    SAP

    Central

    Services,

    or

    SCS).

    The

    enqueue

    server

    transmits

    its

    replication

    data

    to

    an

    enqueue

    replication

    1. Unless

    otherwise

    noted,

    the

    term

    ″z/OS″

    also

    applies

    to

    its

    predecessor,

    OS/390.

    Figure

    1.

    The

    concept

    of

    autonomic